Weft thread retaining and cutting device for shuttleless looms



M. CLAEYS March 21, 1967 WEFT THREAD RETAINING AND CUTTING DEVICE FORSHUTTLELESS LOOMS Filed March 2, 1965 INVENTOR ATTORNEQS United StatesPatent M 3,310,073 WEFT THREAD RETAINING AND CUTTING DEVICE FORSHUTTLELESS LOOMS Marcel Claeys, Lyon, France, assignor to Ofiice Privedes Inventions Modernes O.F.P.R.I.M., Villeurhanne, Rhone, France, aFrench limited-liability company Filed Mar. 2, 1965, Ser. No. 436,477Claims priority, application France, Oct. 13,1964, 45,209, Patent1,419,036 Claims. (Cl. 139-194) This invention relates to a weft threadretaining and cutting device for shuttleless looms of the kind in whichthe woven material has single or double, cut shoots obtained by passingthe weft through the warp threads, not by a shuttle with a weft cop, butby means of a dummy shuttle or other devices of known type.

Said dummy shuttle or the like generally comprises a gripper member forgripping the weft during the movement through the shed, which grippermember is opened at the end of each pick of the dummy shuttle in orderto release the weft thread. During the short space of time between thisgripper opening and the shed closing, the weft thread has a tendency tocurl as soon as released, particularly in the case of highly resilientthreads. This results in an irregular disposition of the weft ends withrespect to the selvedge which produces fraying and gives the fabric abad appearance.

To suppress these drawbacks, it has been proposed to suppress the weftthread tensioning, but this results in another disadvantage. The weftthread goes on through the shed by inertia after opening of the dummyshuttle gripper member and its free end projects out of the fabricselvedge. Said protruding end is pulled back into the shed during thenext pick of the dummy shuttle, which results in a very bad appearanceof the fabric selvedge.

In order to eliminate this new drawback, it has been proposed to placenear the lay a suction nozzle adapted to turn aside the protruding weftend, out of the dummy shuttle path, or to retain it before cutting.

This known method cannot be used on shutteless looms having weftsupplies on both sides, since the suction nozzle would also turn aside,together with the protruding end of the preceding shoot, the next weftthread ready to be woven. Therefore, the dummy shuttle would passwithout catching the said next weft.

An object of this invention is to suppress these drawbacks by realizinga weft retaining and cutting device adapted to be used on shuttlelesslooms having weft supplies indifferently on one side only or on bothsides.

These objects are accomplished in a preferred embodiment of theinvention by securing symmetrically on each end of the lay a unitcomprising: a cylindrical sleeve gas-tightly and slidably mounted withinthe lay main tube; a thrust member rigidly secured to the upper portionof said cylindrical sleeve; a sliding plate moved in a reciprocatingmovement along the said main tube upper side and having a cuttingfront-edge coming into contact with the said thrust member at eachstroke of the said reciprocating movement; an opening provided in theside walls of said cylindrical sleeve and lay main tube, between saidthrust member and said sliding plate cutting edge; said opening beingobturated by the said sliding plate when the cutting edge of the latteris in contact with said thrust member; and suction means connected tothe inner space of said cylindrical sleeve.

The sliding plate is opened when the dummy shuttle comes out of the shedso that the weft free end is aspirated into the cylindrical sleeve,which retains the weft thread and prevents it from curling as long asthe shed has not been closed again. After this operation, that is whenthe Patented Mar. 21, 1967 weft thread is at its definitive positionbetween the warp threads, the sliding plate is shut, thus obturating thesuction opening while cutting the weft protruding free end against thesaid thrust member. This prevents the next weft thread from beingaspirated and turned aside at the next pick of the dummy shuttle.

In the drawings:

FIG. 1 is a diagrammatical view of a device accordin to the invention ona shuttleless loom having weft supplies on both sides, only one weftthread having been illustrated for the clarity of the drawings.

FIG. 2 is a fragmentary cross-section at an enlarged scale, showing adetail of the device object of the invention mounted at one end of thelay, the sliding plate being opened.

FIG. 3 is a section taken on the line III-J11 (FIG. 2).

FIG. 4 corresponds to FIG. 2 when the sliding plate is in closedposition.

The retaining and cutting device shown in FIGS. 1 to 4 is mounted on thelay upper tube 1 of a shuttleless loom of known type having weftsupplies 2 and 3 on both sides. For the clarity of the drawings, onlyone weft thread 4 has been illustrated, delivered by the right weftsupply 3. Each weft thread is inserted through the shed by means of adummy shuttle 5 of known type moved alternately to the right or to theleft above the lay upper tube 1. The dummy shuttle 5 slides on thebottom 6 of a slideway 7 having a U-shaped cross-section. The side wallsof said U-shaped slideway 7 are downwardly turned and welded along thelay upper tube 1.

At each end, the guide bottom 6 and the upr-er wall of tube 1 are slitin longitudinal openings 8 and 9 which may extend up to the end edge oftube 1.

Within tube 1 is slidably mounted a cylindrical sleeve 10 gas-tightlyclosed at both ends in order to define a suction inner space 11. Theside wall of said cylindrical sleeve 10 has an opening 12 located nearits inner end and orientated downwardly. Near the opposite end of saidcylindrical sleeve 10, the side wall of the latter is provided with anopening 13 orientated upwardly. Openings 12 and 13 are diametricallyopposed and located at both ends of the cylindrical sleeve 10. Opening12 is placed in front of the inlet end of a suction tube 14 connected tothe corresponding portion of tube 1.

On the upper portion of cylindrical sleeve 10 are welded a thrust member15 and a guide 16 on which is slidably mounted a sliding plate 17 havinga sharp frontedge 17a. Thrust member 15 and guide 16 are located on bothsides of the opening 13 and they protrude upwardly through thelongitudinal openings 8 and 9; their upper face is in the same plane astheupper face of bottom 6. The sliding plate 17 is ada ted to obturategas-tightly the opening 13 when its cutting edge 17a is in contact withthe thrust member 15. I

According to an important characteristic of the invention, cylindricalsleeve 10 may he slid axially within the lay tube 1 in order to adjustthe loom according to the desired width of the fabric. During thismovement of the cylindrical sleeve 10. the opening 12 is displaced withrespect to the suction tube 14, but vacuum is retained within saidcylindrical sleeve 10 by means of annular sliding seals 18 and =19provided on both sides of tube 14 and opening 12 between the lay maintube 1 and the said cylindrical sleeve 10. Such an adjustment results ina displacement of the thrust member 15 with respect to the lay structure1, 7, said thrust member 15 being slid along the openings 8 and 9.

The sliding plate 17 is horizontal and located near the bottom *6 of theU-shaped slide-way 7. When its cutting edge 17a rests against the thrustmember 15,

3 the space above said sliding plate 17 is no longer subject to thesuction resulting from the vacuum within the suction chamber I l.

Sliding plate '17 is displaced in a reciprocating movement in thedirection indicated by arrow 20, by means of a rotary cam 21 whichactuatcs a bell-crank 22 articulatcd on a spindle Q3 rigidly secured tothe lay. The lower arm of bell-crank 22 is provided with a roller orpush-member 2 ipermanently urged against the rotary earn 21. The upperarm of said bell-crank 22 ends in a fork 2'5 engaged on a transversestub 26 provided on the rear end of sliding plate 17.

According to another important characteristic of the invention, the cam21 has a profile adapted to open the sliding plate 17 above the opening13 when the dummy shuttle 5 comes out of the shed. On the contrary,sliding plate 17 is closed against the thrust member 15, thus obturatingopening 1 3, after the shed has been closed, but prior to the laybeating.

The earns 21 are shifted angularly at 180 with respect to each other onthe shaft 27 (FIG. 1) in order to actuate alternately the sliding plates17 provided on each side of the lay tube 1, according as the dummyshuttle 5 is on the right side or on the left side of the loom.

The angular speed of said cam-shaft 27 is one revolution for twobeating-up strokes of the lay.

The operation is as follows:

When the dummy shuttle 5 gets out of the shed as indicated by the arrow23 (FIG. 1), it moves towards the corresponding shuttle-box after havingreleased the recently woven weft thread 4. The corresponding suctionopening 13 being opened (FIG. 2 and left portion of FIG. 1), the weftend 4a protruding on the side of the fabric is aspirated through saidopening 13. The shed is then closed, which definitively retains the weftthread 4 and prevents the latter from any inopportunc curling orresilient construction. After the shed has been closed, but prior to anew pick of the dummy shuttle, the cam 21 urges the sliding plate 17 asindicated by arrow 20 (FIG. 4). This operation has two results: firstly,the weft end 4a is cut off between the sharp edge 17:: and the thrustmember 15 and secondly, the suction opening 13 is obturatcd, thuspreventing any swerving f the next weft thread, not shown in thedrawings.

After cutting off the weft end 4a (FIG. 4), the latter is removed out ofthe loom, thus preventing any flock accumulation near the fabric. Itwill be appreciated that the weft thread 4 is already positioned withinthe shed after closing of the latter when the weft end 4a is cut off.This permits to obtain a very good seivedge wherein all the weft threadshave exactly the same length.

When the dummy shuttle passes again above the suction opening 13 in thedirection of arrow 2%, said opening 13 is obturated and the next weftthread provided by left weft supply 2 may be caught without difficultybefore being inserted into the shed.

Minor changes may be made without departing from the scope of theinvention as claimed. More particularly, it is possible to actuate theobturating sliding plate by any known system; cams 2'1 and bell-cranks22 could be replaced by electrical, electronical, pneumatic orhydraulical units.

I claim:

1. In a shuttleless weaving loom havin a dummy shuttle and a layprovided with a horizontal main tube, a weft retaining and cuttingdevice at each end of the said lay main tube, comprising the combinationof a cylindrical sleeve gas-tightly and slidably mounted within said laymain tube; a thrust member rigidly secured to the upper portion of saidcylindrical sleeve;'a sliding plate movable in a reciprocating movementalong the upper side of said lay rnain tube and having a cutting frontedge adapted to strike the said thrust member during each stroke of thesaid reciprocating movement; the side walls of said cylindrical sleeveand lay main tube between said thrust member and said sliding platecutting edge having registering openings therein adapted to suctionallyretain the end of the weft thread therein, said openings being closed bythe said sliding plate when the said cutting edge of the latter strikessaid thrust member to sever the end of the weft thread; and suctionmeans connected to the interior of said cylindrical sleeve whilepermitting the sleeve to be moved axially of the main tube to adjust forvarying widths of fabrics.

2. A weft retaining and cutting device as claimed in claim 1, whereinsaid sliding plate is slidably mounted within a guide rigidly secured tothe upper portion of said cylindrical sleeve, said guide and said thrustmember protruding upwardly through said registering openings provided onthe upper wall of said lay main tube and on the bottom of a slidewayfixed to said lay main tube in order to guide the dummy shuttle.

3. A weft retaining and cutting device as claimed in claim 1, whereinsaid sliding plate is slidably mounted within a guide rigidly secured tothe upper portion of said cylindrical sleeve, said guide and said thrustmember protruding upwardly through said registering openings provided onthe upper wall of said lay main tube and on the bottom of a U-shapedslideway opened downwardly and welded by the ends of its side walls tosaid lay main tube in order to guide the dummy shuttle.

4. A weft retaining and cutting device as claimed in claim 1, whereinsaid sliding plate reciprocating movement is obtained by means of acam-shaft having a rotary speed equal to one revolution for twobeating-up strokes of the lay, said camshaft being provided with twocams shifted angularly at with respect to each other as each camactuatcs one of the said combinations mounted on each end of the saidlay main tube.

5. A weft retaining and cutting device as claimed in claim 1, whereinsaid suction means comprise a suction tube rigidly connected to thelower wall of said lay main tube and located in front of a side openingof said cylindrical sleeve, annular sliding seals being provided betweensaid lay main tube and said cylindrical sleeve.

References Cited by the Examiner UNITED STATES PATENTS 1,921,396 8/1933Pool 139194 X 1,963,098 6/1934 Pool 139--194 3,050,088 8/1962 Schatfer139194 X 3,186,444 6/1965 Schafler l39194 X 3,198,216 8/1965 Ancet etal. 139302 3,213,892 10/1965 Fluhmann 139-494 X MERVIN STEIN, PrimaryExaminer.

J. KE E CHI, Assistant Examiner.

1. IN A SHUTTLELESS WEAVING LOOM HAVING A DUMMMY SHUTTLE AND A LAYPROVIDED WITH A HORIZONTAL MAIN TUBE, A WEFT RETAINING AND CUTTINGDEVICE AT EACH END OF THE SAID LAY MAIN TUBE, COMPRISING THE COMBINATIONOF A CYLINDRICAL SLEEVE GAS-TIGHTLY AND SLIDABLY MOUNTED WITHIN SAID LAYMAIN TUBE; A THRUST MEMBER RIGIDLY SECURED TO THE UPPER PORTION OF SAIDCYLINDRICAL SLEEVE; A SLIDING PLATE MOVABLE IN A RECIPROCATING MOVEMENTALONG THE UPPER SIDE OF SAID LAY MAIN TUBE AND HAVING A CUTTING FRONTEDGE ADAPTED TO STRIKE THE SAID THRUST MEMBER DURING EACH STROKE OF THESAID RECIPROCATING MOVEMENT; THE SIDE WALLS OF SAID CYLINDRICAL SLEEVEAND LAY MAIN TUBE BETWEEN SAID THRUST MEMBER AND SAID SLIDING PLATECUTTING EDGE HAVING REGISTERING OPENINGS THEREIN ADAPTED TO SUCTIONALLYRETAIN THE END OF THE WEFT THREAD THEREIN, SAID OPENINGS BEING CLOSED BYTHE SAID SLIDING PLATE WHEN THE SAID CUTTING EDGE OF THE LATTER STRIKESSAID THRUST MEMBER TO SEVER THE END OF THE WEFT THREAD; AND SUCTIONMEANS CONNECTED TO THE INTERIOR OF SAID CYLINDRICAL SLEEVE WHILEPERMITTING THE SLEEVE TO BE MOVED AXIALLY OF THE MAIN TUBE TO ADJUST FORVARYING WIDTHS OF FABRICS.